1. Field of the Invention
The present invention relates to a mobile communication device and an antenna structure thereof, and more particularly, to a mobile communication device and an antenna structure with a built-in multiband antenna capable of being integrated with a ground plane configured with an external data transmission element.
2. Description of the Prior Art
With the progress of wireless technology, the wireless communication industry has benefited. Mobile communication devices are required to be light and small, such that small size, multi-band operations, as well as the integration of an internal antenna and other electronic elements on the system circuit board of the device become essential design considerations. However, in order to obtain wideband operation and perform the integration of an internal antenna and other electronic elements on the system circuit board of the device, conventional antennas in the mobile communication devices directly dispose its antenna in the no-ground section of the system circuit board of the device, such that coupling effects between the antenna and the grounding plane can be reduced and sufficient operating bandwidth can be provided to cover the wideband WWAN operation. However, such WWAN antenna is mostly disposed on a single no-ground section of the system circuit board, which may reduce the design freedom of the internal electronic elements of the mobile communication device.
In the prior art, such as U.S. Pat. No. 7,768,466 B2 with the invention entitled “Multiband folded loop antenna”, a mobile antenna occupying the three-dimensional space is disclosed, whose antenna is disposed on a single no-ground section to achieve wideband operation. However, by adopting such antenna configuration, the integration of the antenna and other electronic elements functioning as a data transmission port (such as, a USB connector) of the mobile communication device cannot be achieved, which results in an inefficient configuration of the internal space of the mobile communication device. In addition, its operating band cannot cover the eight-band LTE/WWAN operation, including LTE700/GSM850/900/1800/1900/UMTS/LTE2300/2500, which cannot satisfy requirements of covering operating bands of all mobile communication systems at present.
Hence, how to provide a mobile communication device with two wide operating bands at least covering from about 704 MHz to 960 MHz and from about 1710 MHz to 2690 MHz to satisfy the eight-band LTE/WWAN operation and perform the integration of an internal antenna and other electronic elements on the system circuit board of the device has become an important topic in this field.